Sony DB9930 Receiver Protect Mode

[Joe Turner]

My Sony DB930 goes into 'Protect Mode' when it is turned on. This still happens even after all speaker wires, etc are disconnected. When this initially happened a month or two ago, I reconnected all the speaker wires which temporarily resolved the problem--it worked fine. Now it has returned. Any idea of what I can try before I take it in to a service center? I have read something about checking multiple fuses(?), but given the fact that the problem stopped and re-started again, was unsure if a fuse still made sense or if it would likely be something else.

I am an electronics novice, so while I'm willing to try whatever to attempt a fix, I do not have a lot of electronic diagnostic equipment. Also while I think this is generally considered to be a very good receiver, I'm not sure how much money I should put into repairing it as it is nearly 13 years old. Any advice on any of this would be greatly appreciated!

 

[master7045]

I had a Yamaha receiver that would go into protect mode and it was either due to overheating (was in a small cabinet at the time) and was to the touch hot. The other time was when the exposed copper speaker wires (+ & -) would touch, which would cause it to shutdown. I'd take a close look at the speaker terminals on the backside of that receiver and make sure there aren't any loose strands of speaker wire that may be causing the short.

 

[Joe Turner]

I had a Yamaha receiver that would go into protect mode and it was either due to overheating (was in a small cabinet at the time) and was to the touch hot. The other time was when the exposed copper speaker wires (+ & -) would touch, which would cause it to shutdown. I'd take a close look at the speaker terminals on the backside of that receiver and make sure there aren't any loose strands of speaker wire that may be causing the short.

Appreciate the feedback, but I don't think those are the issue because:
1) I've disconnected all the speaker wires and it still goes into protect mode;
2),The receiver has been in the same place for five years (relatively well ventilated). regardless, as it happens immediately upon power up, pretty sure it's not overheating issue.

 

[master7045]

I agree it's probably not #1. I'd still check the speaker terminals to see if a loose strand got stuck somehwere. That's what happened to me, upon close inspection I found a single copper "string" that was connecting the positive & negative terminals. If thats not it, I don't really know. You can try to download or look in the manual. Usually there is a t/s section with a description of the error messages.

 

[Number1]

Joe, this sound like an internal problem, Disconnect the unit, take the cover off and blow compressed air to dislodge dirt and dust bunies. Check to see if there are any blown fuses, bulging capacitors, sign of overheating etc.

Once clean and if nothing looks abnormal, power it back up and see if the problem is gone.

Chance are you need a new receiver but you might get lucky.

Let us know how it went.

 

[Joe Turner]

I agree it's probably not #1. I'd still check the speaker terminals to see if a loose strand got stuck somehwere. That's what happened to me, upon close inspection I found a single copper "string" that was connecting the positive & negative terminals. If thats not it, I don't really know. You can try to download or look in the manual. Usually there is a t/s section with a description of the error messages.

Joe, this sound like an internal problem, Disconnect the unit, take the cover off and blow compressed air to dislodge dirt and dust bunies. Check to see if there are any blown fuses, bulging capacitors, sign of overheating etc.

Once clean and if nothing looks abnormal, power it back up and see if the problem is gone.

Chance are you need a new receiver but you might get lucky.

Let us know how it went.

Thanks for the ideas guys. Appreciate the suggestions.
@Number1 I opened the unit up and used the compressed air to clean off whatever I could. I didn't see any obvious sign of failure, but I honestly may not know what to look for outside of the very obvious.

After closing unit and plugging it back in I got the same Protect message. However I tried restarting several more times and it finally started properly-no protect message. So, it's currently working right now, but I am relatively sure this is a temporary fix. But it is interesting that once it gets past the "power-up stage", it seems to operate just fine. Perhaps I should just never turn it off, eh? But I am guessing I should probably start shopping for new receivers.